Electronic recording of pressure exerted by cows against structures in free-stall housing

Pressure exerted by cows against the feeding rail and side rails, neck rail and brisket board of cubicles was recorded by means of pressure transducers. Video surveillance was used to examine the nature of the body contact.Pressure during feeding was recorded during a normal and a contrived situation at the feeding table, and during feeding from a manger elevated 16–18 cm above floor level. Forty-three percent of recordings were above 50 kg during the contrived situation and 8% when feeding from the standard manger.In the cubicle, side rails were leant against most often. The resting cow pressed more frequently on the left side rail than on the right one, viz. 28 vs. 10% of recordings over 50 kg. Occasionally, cows bumped the brisket board with their front legs. This could result in contusions to the knees. The neck rail was only occasionally touched by the cows.     

The influence of root-zone temperature on growth of Betula pendula Roth.

We have examined shoot and root growth and the concentration of carbohydrates in seedlings of a northern (67°N) and a southern (61°N) ecotype of Betula pendula Roth. cultivated at root-zone temperatures of 2, 6, 12 and 17°C. Three hydroponic experiments were conducted in controlled environments. We used three different pretreatments before seedlings were subjected to the experimental temperature treatments. Actively growing seedlings that were acclimated to the hydroponic solution for 3 weeks at a root temperature of 17°C, continued to grow at all the experimental temperatures, with an expected increase in growth from 2 to 17°C. However, if we started with ecodormant cold stored plants or used seedlings grown actively in perlite, no growth was observed at 2°C and only minor growth was found at 6°C. The highest root temperature always produced the best growth. The concentration of nonstructural carbohydrates was higher in seedlings grown at 2°C than at 17°C, and this is probably due to extensive incorporation of carbohydrates into cell walls and other structural elements at 17°C. We found no evidence for differences between the two ecotypes in root growth, in timing of bud burst, but shoot growth terminated in the northern ecotype in the first experiment because the natural photoperiod was below the critical value. Our study highlights the importance of post-transplantation stress (planting check) related to root growth, and that root threshold temperatures may change according to the way plants are pretreated.